(1) Technical Field
This invention relates to locking systems for vehicle doors of the kind in which a central control unit is connected to the individual locks for electrical actuation of the latter whereby locking or unlocking of all the doors can be effected from a single control station actuated from within or outside the vehicle, hereinafter referred to as "central locking systems" and more specifically to the provision in the system of a dead-locking or super-locking facility by which the lock mechanism is selectively positively retained at the secure position so that it cannot be freed by use of any of the manual actuating means within or outside the vehicle.
(2) Description of the Prior Art
Vehicle door locking systems of the subject invention are increasingly desirable for improving the security of unattended vehicles so that a lock cannot readily be released by forcing a window or using a probe, hook or other tool to gain access to the interior door handles, sill release buttons or the like.
One example of a central locking system to which the invention is conveniently applicable is described in our GB Pat. No. 2176528.
The object of the invention is to provide a central locking system with a remotely controllable dead-locking facility which is economical to produce, compact so that it can be accommodated in known patterns of lock actuator units without increasing their bulk and/or without substantial redesign thereof, yet which is positive and reliable in use and of simple and durable construction.